Abstract : Characterization of the trifluoronitrosomethane/tetrafluoroethylene copolymer was continued. The CF3NO/C2F4 copolymer was found to be adaptable to elution fractionation in a perfluorocyclic ether and a benzotrifluoride solvent/nonsolvent system. A weight-viscosity distribution consisting of 25 fractions was obtained. A sample from which 25% insoluble gel was removed exhibited two dominant molecular weight regions of 2 x 10 to the 5th power and 4 x 10 to the 6th power. The molecular weight of a fraction of the CF3NO/C2F4 copolymer with a reduced viscosity of 1.37 in perfluorocyclic ether was determined by light scattering to be 2.1 x 10 to the 6th power. An amine cured CF3NO/C2F4 sample was swollen by fourteen solvents and chemicals, including water. No crystallinity was observed in the CF3NO/C2F4 gum down to -80C. (Author)